I will provide a couple of character traits of The Nurse, according to eNotes' Romeo and Juliet study guide and I will give some places where you can find evidence for them:

The Nurse is bawdy and vulgar. She doesn't worry about being proper or polite even around her master or mistress. So when we first see her in Act I, Scene 3, she swears "by my maidenhead, at twelve year old." This is clear evidence of her being bawdy -- you wouldn't think someone would refer to sexual matters around their boss.

She talks a lot and in a sometimes confused manner. Later on in this scene, Juliet's mother talks about how old Juliet is and The Nurse goes off on this long discussion of how she knows how old Juliet is. Finally, Lady Capulet has to just tell her to shut up.

These seem to me to be her two greatest character traits if you are just talking about what she's like as a person, as opposed to how people see her, etc.